Hydraulic bump stop assembly

ABSTRACT

Embodiments of a hydraulic bump stop assembly may include a telescoping hydraulic cylinder containing hydraulic fluid. The telescoping cylinder may be located on a vehicle shock. Components of the shock may engage and compress the telescoping cylinder during the final stages of compression of the shock to prevent the shock from bottoming out. The telescoping cylinder has damping properties during compression and expansion due to hydraulic fluid being forced through orifices of one or more hydraulic fluid lines to and from a reservoir. Damping ratios may be adjusted by adjusting the size of the orifices. In some embodiments, the damping ratios may be adjusted remotely, such as from the driver compartment of the vehicle.

CROSS REFERENCE TO RELATED APPLICATION[S]

This application is a divisional of U.S. Patent Application entitled“HYDRAULIC BUMP STOP ASSEMBLY,” Ser. No. 18/053,067, filed Nov. 7, 2022,which is a divisional of U.S. Patent Application entitled “HYDRAULICBUMP STOP ASSEMBLY,” Ser. No. 17/230,439, filed Apr. 14, 2021, now U.S.Pat. No. 11,493,106, issued Nov. 8, 2022, which claims priority to U.S.Provisional Patent Application entitled: “HYDRAULIC BUMP STOP ASSEMBLY,”Ser. No. 63/009,857, filed Apr. 14, 2020, the disclosures of which arehereby incorporated entirely herein by reference.

TECHNICAL FIELD

This invention relates generally to vehicle suspension systems andparticularly to a hydraulic bump stop assembly configured to be coupledto a shock of a vehicle.

BACKGROUND

When a vehicle is driven over bumps or rough terrain, the suspensionsystem may bottom out. Bottoming out may include a shock absorber beingcompressed to the fullest extent. Bottoming out of a shock may causedamage to the shock and/or to other vehicle components, in addition tocausing an uncomfortable, or even dangerous, ride for passengers.

To prevent bottoming out, some conventional shock absorbers haveintegrated bump stops that serve as a suspension cushion to keep shockparts from coming together or from traveling too far. These aretypically made of rubber or urethane, or other similar material forabsorbing shock, and are formed with a through hole for coupling aroundthe shaft of the shock. They are sized appropriately to be engagedduring only the last portion of travel of the shock during the finalstages of compression. Some are “stepped” to provide incremental dampingand spring ratios as they are compressed. A disadvantage of aconventional rubber or urethane bump stop is that it dissipates energyinto the suspension rebound, causing stress on the shock. These bumpstops offer little damping and often behave much like a pure coilspring.

An alternative that has become popular in recent years is a gaspressurized nitrogen bump stop (often called an air bumps or hydraulicbump stop). These cylindrical units consist of a short stroke shockmechanism that is velocity sensitive. Oil is used inside and movesthrough orifices much like a standard shock. This allows the bump toeffectively dampen, or slow, the suspension movement through its finalinches of travel. In contrast with an air or gas shock, they have largeshaft diameters and are much shorter. Hydraulic bump stops also exhibitsome rebound dampening as well. Conventional hydraulic bump stops arenot integrated components of a shock. They are typically mountedseparately to the vehicle suspension system and operate independentlyfrom the shock absorbers of the vehicle. This takes up additional spaceon the vehicle, requires additional labor and significant cost formaterials and labor. In addition, many vehicle racing organization rulesprohibit these hydraulic bump stops separate from the shocks.

SUMMARY OF THE INVENTION

The present invention relates to vehicle suspension systems andparticularly to a hydraulic bump stop assembly configured to be coupledto a shock of a vehicle. Some embodiments may comprise a shock with ahydraulic bump stop coupled thereto. In one embodiment, a hydraulic bumpstop comprises an outer hydraulic cylinder and an inner hydrauliccylinder operationally coupled to, and coaxial with, the outer hydrauliccylinder. The inner cylinder slidingly engages the outer cylinder, andthe outer hydraulic cylinder and the inner hydraulic cylinder define atelescoping cylinder interior volume. The hydraulic bump stop furthercomprises a fluid reservoir, in fluid communication with the telescopingcylinder interior volume through at least one orifice.s

Embodiments of a hydraulic bump stop assembly may comprise a telescopinghydraulic cylinder comprising an outer hydraulic cylinder and an innerhydraulic cylinder operationally coupled to, and coaxial with, the outerhydraulic cylinder, wherein the inner cylinder slidingly engages theouter cylinder in a telescoping fashion. Each of the inner and outercylinders has an inner volume for containing hydraulic fluid, whereinthe combined inner volume may expand or contract with extension orcontraction of telescoping cylinder, respectively, by sliding of theinner cylinder, in a telescoping fashion, in or out, relative to theouter cylinder. In some embodiments, without limitation, a telescopinghydraulic cylinder may comprise additional concentric telescopingmembers. The telescoping cylinder may comprise a seal coupled betweeneach of the adjoining telescoping members.

In some embodiments, the telescoping cylinder may be configured to becoupled to a shock of a vehicle. Some embodiments comprise a vehiclewith a shock having a telescoping hydraulic cylinder coupled thereto.

The telescoping cylinder has a damping effect during compression andexpansion. The telescoping cylinder may be configured to be coupled to ashock of a vehicle, such that components of the shock engage thetelescoping cylinder during final stages of compression of the shock toprevent the shock from bottoming out. During compression and expansionof the telescoping cylinder, hydraulic fluid is expelled from or drawninto the telescoping cylinder, respectively, through at least oneorifice between the telescoping cylinder and at least one hydraulicfluid line for carrying hydraulic fluid between the telescoping cylinderand a reservoir. This gives the telescoping cylinder a damping effectboth during compression and expansion.

Damping ratios may be adjustable or controllable by a user by changingthe cross-sectional area of the at least one orifice. In someembodiments, the means of controlling adjustment of the damping ratiomay be remote, such as from a control located within the drivercompartment of the vehicle.

The foregoing and other features and advantages of the present inventionwill be apparent from the following more detailed description of theparticular embodiments of the invention, as illustrated in theaccompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

A more complete understanding of the present invention may be derived byreferring to the detailed description and claims when considered inconjunction with the Figures, wherein like reference numbers refer tosimilar items throughout the Figures, and:

FIG. 1A is a front view of a shock absorber comprising a hydraulic bumpstop assembly, according to an embodiment;

FIG. 1B is a front section view of a h shock absorber comprising ahydraulic bump stop assembly, according to an embodiment;

FIG. 1C is a close-up front section view of a hydraulic bump stopassembly, according to an embodiment;

FIG. 1D is a top view of a hydraulic bump stop assembly, according to anembodiment;

FIG. 2A is a front view of a shock absorber comprising a hydraulic bumpstop assembly, according to an embodiment;

FIG. 2B is a front section view of a shock absorber comprising ahydraulic bump stop assembly, according to an embodiment;

FIG. 2C is a close-up front section view of a hydraulic bump stopassembly, according to an embodiment;

FIG. 2D is a top view of a hydraulic bump stop assembly, according to anembodiment;

FIG. 3A is a front view of a shock absorber comprising a hydraulic bumpstop assembly, according to an embodiment;

FIG. 3B is a front section view of a shock absorber comprising ahydraulic bump stop assembly, according to an embodiment;

FIG. 3C is a close-up front section view of a hydraulic bump stopassembly, according to an embodiment;

FIG. 3D is a front view of a shock absorber comprising a hydraulic bumpstop assembly, according to an embodiment;

FIG. 3E is a top view of a hydraulic bump stop assembly, according to anembodiment;

FIG. 4A is a front view of a shock absorber comprising a hydraulic bumpstop assembly, according to an embodiment;

FIG. 4B is a front section view of a shock absorber comprising ahydraulic bump stop assembly, according to an embodiment;

FIG. 4C is a close-up front section view of a hydraulic bump stopassembly, according to an embodiment; and

FIG. 4D is a top view of a hydraulic bump stop assembly, according to anembodiment.

DETAILED DESCRIPTION OF EMBODIMENTS OF THE INVENTION

As discussed above, embodiments of the present invention relate tovehicle suspension systems and particularly to a hydraulic bump stopassembly configured to be coupled to a shock of a vehicle. Someembodiments may comprise a shock with a hydraulic bump stop coupledthereto.

FIG. 1A is a front view of a shock absorber 10 comprising a hydraulicbump stop assembly, according to an embodiment. Embodiments of a shockabsorber 10 comprising a hydraulic bump stop assembly may comprise atelescoping hydraulic cylinder 12 comprising an outer hydraulic cylinder14 and an inner hydraulic cylinder 16 operationally coupled to, andcoaxial with, the outer hydraulic cylinder 14, wherein the innercylinder 16 slidingly engages the outer cylinder 14 in a telescopingfashion. FIG. 1B is a front section view of shock absorber 10 comprisinga hydraulic bump stop assembly, according to an embodiment. Each of theinner and outer cylinders 16 and 14 has an inner volume for containinghydraulic fluid 24, wherein the combined inner volume 20 may expand orcontract with extension or contraction of telescoping cylinder 12,respectively, by sliding of the inner cylinder 16, in a telescopingfashion, in or out, relative to the outer cylinder 14. The telescopingcylinder 12 may comprise a seal 22 coupled between the inner and outercylinders 16 and 14.

It is to be understood, for purposes of this application, that“hydraulic fluid” may refer to liquid hydraulic fluid, or to any otherliquid or gas that may be suitable for use in any hydraulic or pneumaticpiston cylinder.

The telescoping cylinder 12 may be coupled to and in fluid communicationwith at least one hydraulic fluid line 26 for carrying hydraulic fluid24 between the telescoping cylinder 12, at one end of the at least onehydraulic fluid line 24, and a reservoir 28 coupled to and in fluidcommunication with the at least one hydraulic fluid 26 at the oppositeend thereof. In some embodiments, the reservoir 28 may be anaccumulator. When the telescoping hydraulic cylinder 12 is compressed, aportion of the hydraulic fluid 24 within the telescoping hydrauliccylinder 12 is expelled through the at least one hydraulic fluid line 26and into the reservoir 28. Resistance of hydraulic fluid 24 being forcedthrough at least one orifice 30 between the telescoping cylinder 12 andeach of the at least one hydraulic fluid line 26 creates a dampingeffect when the hydraulic cylinder 12 is compressed, the damping ratioof which is determined by the cross-sectional area of the at least oneorifice 30. In reverse, as the telescoping cylinder 12 is expanded, alsoknown as “rebound,” a rebound damping effect is also determined by thecross-sectional area of the at least one orifice 30 through whichhydraulic fluid 24 returns into the telescoping cylinder 12.

In some embodiments, hydraulic fluid 24 may exit from and return to thetelescoping cylinder 12 through the same orifice 30. In someembodiments, hydraulic fluid 24 may return to the telescoping cylinder12 through a different orifice 30, having a different cross-sectionalarea from the cross-sectional area of the orifice 30 through which itwas expelled. In such embodiments, the compression damping ratio may bedifferent from the rebound damping ratio, wherein each of thecompression damping ratio and the rebound damping ratio may becontrolled independently based on the cross-sectional areas of therespective orifices 30. In some embodiments, the orifices 30 may beadjustable in cross sectional area, whether by a manual adjustmentmeans, or by an automatic adjustment means, such as by an actuator,whether electronic or otherwise (not shown).

In some embodiments, without limitation, a telescoping hydrauliccylinder 12 may comprise additional concentric telescoping members 18.For example, a telescoping hydraulic cylinder 12 may comprise an outercylinder 16, an inner cylinder 14, and at least one intermediatecylinder 18 operationally coupled between the outer cylinder 14 and theinner cylinder 16 in a telescoping fashion, with a seal 22 being coupledbetween each of the adjoining members. Greater lengths of travel, duringcompression and rebound, may thus be achieved by integration ofadditional telescoping cylinder members 18. In addition, use ofadditional cylinder members 18 creates a stepped damping ratio, as thedamping ratio steps up during compression as each successive telescopingcylinder member is compressed and the next successive telescopingcylinder member is engaged, beginning with the inner cylinder 16, untilthe outer cylinder 14 is engaged. This is due to the increasingly largercross-sectional area of each successively larger diameter cylinder,resulting in a greater volume rate of flow of hydraulic fluid 24 beingforced through the at least one hydraulic fluid line 26. The reverse istrue during rebound, wherein the damping ratio steps down with expansionof each successive telescoping member.

Embodiments of a telescoping hydraulic cylinder 12 of a hydraulic bumpstop assembly 10 may be configured to be coupled to a shock 32 of avehicle. For example, a telescoping hydraulic cylinder 12 may have alongitudinal central aperture 34 therethrough, through which a main rod36 of a shock 32 may extend. In some embodiments, a telescopinghydraulic cylinder 12 may be coupled to the bottom end 38 of a hydraulicpiston cylinder 40 of a shock 32, wherein the main rod 36 extendsthrough the central aperture 34 of the telescoping hydraulic cylinder12, the main rod 36 being able to slide through the central aperture 34as the shock 32 is compressed and expanded. As the shock 32 iscompressed, the main rod 36 slides through the central aperture 34 untilthe bottom perch 42 of the shock 32 engages the inner cylinder 16 of thetelescoping hydraulic cylinder 12. The telescoping hydraulic cylinder 12provides some resistance and a damping effect until the inner cylinder16 is compressed and the next successive telescoping cylinder member isengaged by the bottom perch 42. Each successive telescoping cylindermember is engaged, in turn, and compressed, until the bottom perch 42engages the outer cylinder 14, if at all. As described above, thedamping ratio is increased as each successive telescoping cylinder 12 isengaged by the bottom perch 42.

In such embodiments, the reservoir 28 may be that portion of theinterior volume 44 of the piston cylinder 40 of the shock 32 below thepiston 46, wherein the at least one hydraulic fluid line 26 is in fluidcommunication with the interior volume 44 of the piston cylinder 40 ofthe shock 32 below the piston 46. In such embodiments, the interiorvolume 44 of the piston cylinder 40 of the shock 32 below the piston 46increases as the shock 32 is compressed, tending to draw hydraulic fluid24 from the telescoping cylinder 12. However, the rate of flow ofhydraulic fluid 24 is relatively slow until such point as the bottomperch 42 engages the telescoping cylinder 12 and begins to compress thetelescoping cylinder 12. As the shock 32 is extended during rebound,hydraulic fluid 24 is expelled from the piston cylinder 40 and back intothe telescoping cylinder 12 to expand the telescoping cylinder 12 again.The rate of expansion of the telescoping cylinder 12 during rebound iscontrolled because of the damping effect due to the cross-sectional areaof the at least one orifice 30.

In other embodiments, the telescoping hydraulic cylinder 12 may bedisposed at a different location on the shock 32. For example, it may bedisposed at the lower end 48 of the main rod 36, and coupled to thebottom perch 42, as shown in FIGS. 2A-C. In such embodiments,compression of the telescoping cylinder 12 begins when the bottom end 38of the piston cylinder 40 of the shock 32 comes into contact with andengages the telescoping cylinder 12 during compression of the shock 32.In such embodiments, the at least one hydraulic fluid line 26 may bedisposed internally to the main rod 36, wherein the at least onehydraulic fluid line 26 is in fluid communication with the telescopinghydraulic cylinder 12 at one end and that portion of the internal volume44 of the piston cylinder 40 of the shock 32 above the piston 46 at theother end, wherein that portion of the internal volume 44 of the pistoncylinder 40 of the shock 32 above the piston 46 is the reservoir 28. Insome such embodiments, the at least one hydraulic fluid line 26 may bealternatively in fluid communication with the telescoping hydrauliccylinder 12 at one end and the reservoir of the shock 32 at the otherend, as shown in FIGS. 3A-B, wherein the reservoir of the shock is thereservoir 28. In yet other embodiments, the at least one hydraulic fluidline 26 may be alternatively in fluid communication with the telescopinghydraulic cylinder 12 at one end and a separate reservoir at the otherend, as shown in FIG. 3D, wherein the separate reservoir is thereservoir 28.

In some embodiments, the telescoping hydraulic cylinder 12 may bedisposed within the interior volume 44 of the piston cylinder 40 of theshock 32, above the piston 46, and may be coupled, for example, to theupper end 50 of the interior 44 of the piston cylinder 40, as shown inFIGS. 4A-C. In such embodiments, compression of the telescoping cylinder12 begins when the piston 46 of the piston cylinder 40 of the shock 32comes into contact with and engages the telescoping cylinder 12 duringcompression of the shock 32. In such embodiments, the at least onehydraulic fluid line 26 may be in fluid communication with thetelescoping hydraulic cylinder 12 at one end and the reservoir 28 of theshock 32 at the other end, as shown in FIGS. 4B-C, wherein the reservoirof the shock is the reservoir 28.

Regardless of the particular configuration or disposition of thetelescoping hydraulic cylinder 12 coupled to the shock 32, the dampingratios of the telescoping hydraulic cylinder 12 may be adjustable byinterchanging the at least one orifice 30 between the telescopinghydraulic cylinder 12 and the at least one hydraulic fluid line 26, orby adjusting such at least one orifice 30 that may be adjustable. Insome embodiments, adjustment of an at least one adjustable orifice 30may be performed remotely, such as from a control disposed within thedriver compartment of the vehicle (not shown). In some embodiments, themeans of adjustment of the at least one adjustable orifice 30 may bethrough a mechanical linkage, or by wire, or wireless (not shown).

In some embodiments, a hydraulic bump stop assembly 10 may comprise ashock 32 with a telescoping hydraulic cylinder 12 coupled to the shock32; and at least one hydraulic fluid line 26 coupled between thetelescoping hydraulic cylinder 12 and a reservoir 28, wherein theparticular embodiment of the telescoping hydraulic cylinder 12 and theat least one hydraulic fluid line 26 may be any of those embodimentsdescribed above that are configured to be coupled to a vehicle shock 32.

The components defining any hydraulic bump stop assembly may be formedof any of many different types of materials or combinations thereof thatcan readily be formed into shaped objects provided that the componentsselected are consistent with the intended operation of a hydraulic bumpstop assembly. For example, the components may be formed of: rubbers(synthetic and/or natural) and/or other like materials; glasses (such asfiberglass), carbon-fiber, aramid-fiber, any combination thereof, and/orother like materials; polymers, such as thermoplastics (such asacrylonitrile butadiene styrene (ABS), fluoropolymers, polyacetal,polyamide; polycarbonate, polyethylene, polysulfone, and/or the like),thermosets (such as epoxy, phenolic resin, polyimide, polyurethane,silicone, and/or the like), any combination thereof, and/or other likematerials; composites and/or other like materials; metals, such ascopper, zinc, magnesium, titanium, copper, iron, steel, carbon steel,alloy steel, tool steel, stainless steel, aluminum, any combinationthereof, and/or other like materials; alloys, such as aluminum alloy,titanium alloy, magnesium alloy, copper alloy, any combination thereof,and/or other like materials; any other suitable material; and/or anycombination thereof.

Furthermore, the components defining any hydraulic bump stop assemblymay be purchased pre-manufactured or manufactured separately and thenassembled together. However, any or all of the components may bemanufactured simultaneously and integrally joined with one another.Manufacture of these components separately or simultaneously may involveextrusion, pultrusion, vacuum forming, injection molding, blow molding,resin transfer molding, casting, forging, cold rolling, milling,drilling, reaming, turning, grinding, stamping, cutting, bending,welding, soldering, hardening, riveting, punching, plating, and/or thelike. If any of the components are manufactured separately, they maythen be coupled with one another in any manner, such as with adhesive, aweld, a fastener (e.g. a bolt, a nut, a screw, a nail, a rivet, a pin,and/or the like), wiring, sewing, any combination thereof, and/or thelike for example, depending on, among other considerations, theparticular material forming the components. Other possible steps mayinclude sand blasting, polishing, powder coating, zinc plating,anodizing, hard anodizing, and/or painting the components, for example.

The embodiments and examples set forth herein are presented in order tobest explain illustrative embodiments and illustrative practicalapplications thereof, and to thereby enable those of ordinary skill inthe art to make and use illustrative embodiments. However, those ofordinary skill in the art will recognize that the foregoing descriptionand examples have been presented for the purposes of illustration andexample only. The description as set forth is not intended to beexhaustive or to limit the invention to any of the particular forms,embodiments, materials, or steps disclosed above. Many modifications andvariations are possible in light of the teachings above withoutdeparting from the spirit and scope of the forthcoming claims.

What is claimed is:
 1. A hydraulic bump stop comprising: an outerhydraulic cylinder coupled to a bottom end of a hydraulic pistoncylinder of a shock absorber; and an inner hydraulic cylinderoperationally coupled to, and coaxial with, the outer hydrauliccylinder, wherein the inner cylinder slidingly engages the outercylinder, and wherein the outer hydraulic cylinder and the innerhydraulic cylinder define a telescoping cylinder interior volume,wherein an interior volume of the hydraulic piston cylinder of the shockabsorber is in fluid communication with the telescoping cylinderinterior volume through at least one orifice.
 2. The hydraulic bump stopof claim 1, further comprising a means of adjusting a cross-sectionalarea of the at least one orifice, thereby controlling a damping ratio ofthe hydraulic bump stop.
 3. The hydraulic bump stop of claim 2, furthercomprising a remote means of controlling the means of adjusting thecross-sectional area of the at least one orifice.
 4. The hydraulic bumpstop of claim 3, wherein the hydraulic bump stop is configured to becoupled to the shock absorber, which is coupled to a vehicle, andwherein the remote means is positioned in a driver compartment of thevehicle.
 5. The hydraulic bump stop of claim 4, wherein the at least oneorifice comprises at least one compression orifice and at least oneexpansion orifice, wherein the at least one compression orifice definesa compression damping ratio, and the at least one expansion orificedefines an expansion damping ratio.